This application claims the priority of Italian application TO 96 A 000247 filed Mar. 29, 1996 in Italy, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a guide for a selector lever for a gearbox, in which the selector lever is movable in two gear-shift gates which are parallel to each other and which are connected by a transverse gate.
A selector lever of this type is already known from European Patent Document EP O 331 797 Bl. The selection device shown there for an automatic gearbox has a selector lever which is pivotable in two gear-shift gates. When the selector lever is in the first gear-shift gate it acts directly upon the automatic gearbox by means of a transmission device. When the selector lever is shifted into the second gear-shift gate it is detached from the transmission device, and a locking device prevents the transmission device from being moved in an undesired manner out of the intended position.
Other generally known selector-lever guides, such as for example the guidance of the selector lever in a guide slot in a cover, have such large tolerances that a precise guidance of the selector lever is not possible.
An object of the invention is to guide a selector lever in such a way as to ensure a reliable positioning of the selector lever on leaving the first gear-shift gate and on re-entering the first gear-shift gate.
It is proposed according to the invention to design a guide for the selector lever with the aid of a structural member which is arranged immediately adjacent to the selector lever. This structural member has a face which extends in a plane parallel to the plane of movement of the selector lever. A guide member provided directly on the selector lever engages over the structural member and rests against the side of the face remote from the selector lever, so that the selector lever is guided in the plane of movement thereof. For the transverse movement of the selector lever, an aperture is provided at that point on the face at which the guide member is present when the selector lever is at the level of the transverse gate. A guide formed in this way for a selector lever is simple in design, is simple to assemble without requiring additional adjustment, and can be manufactured in an expedient manner without the precision of the guidance of the selector lever being adversely affected in this case.
The preferred embodiments of the invention include further advantageous features. In this connection, it is proposed that the width of the aperture should correspond to the width of the guide member, and the length of the aperture should be adapted to the movement requirement of the selector lever for pivoting from the first gear-shift gate into the second gear-shift gate, in such a way that a longitudinal displacement of the selector lever is possible again only when the said selector lever has reached the second gear-shift gate. Since it is now impossible to move the selector lever out of the second gear-shift gate into an undefined position, the precision of the guidance of the selector lever is further improved.
The guidance of the selector lever can be further improved by constructing the guide as part of the housing of the selection device. It is therefore unnecessary to adjust the guide.
The guide is preferably arranged in such a way that it comes to rest below a cover for the selection device. In this way, it is protected from soiling and damage, and foreign bodies are prevented from penetrating into the guide and obstructing the movement of the selector lever.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.